THE HAEMOFLAGELLATES 



215 



is even more elaborate in the former parasite than in the case just 

 described. Further evidence in support of Schaudinn's view of 

 the intimate relation and correspondence between the two nuclear 

 organellae is furnished by Leger (50), who has observed, In 

 "ookinetes" of T. barbatulae (see under "Life-Cycle"), heteropolar 

 division of a single large nucleus, doubtless leading to the forma- 

 tion of tropho- and Idnetonucleus ; and by Bradford and Plimmer 

 (6), who have observed the latter element (" micronucleus ") T given 

 off from the larger nucleus in T. brucii. Perhaps the most striking 

 confirmation of the essential nuclear character of the kinetonucleus 

 is afforded, however, by a comparison of this organella in Trypano- 

 plasma b&rreli, where it is particularly large, and like a nucleus ; in 

 fact, it was originally regarded as the nucleus (trophonucleus) of 



FIG. 11. 



Trypanoplasma borreM, Lav. and Mesn. a./, anterior flagellum ; p.f, posterior flagellum ; m, 

 undulating membrane ; T, trophonucleus ; K, kinetonucleus ; /, fibril (myoneme) ; c, centro- 

 somic granule at base of flagellum. (After Leger.) 



this parasite. Moreover, in addition to the kinetonucleus, and 

 immediately in front of it, two centrosomic granules can be 

 distinctly seen, one at the base of each flagellum (shown clearly in 

 Leger's figures, Fig. 11, B, c). In Trypanosoma also, in many cases, 

 the root of the flagellum is not actually connected with the kineto- 

 nucleus, but terminates before reaching it in an unmistakable 

 granule, which we have found to stain much darker than the 

 flagellum. Lastly, in this connection the writer has been very kindly 

 permitted by Prof. Minchin to make use of two figures of his (about 

 to be published) of Trypanosoma grayi undergoing division, in which 

 centrosomic granules, associated with the kinetonuclei, are clearly 



1 It is necessary to point out that the kinetonuclens is not a "inicromicleus," 

 in the sense in which this term is always used as applying to that body in the 

 Infusoria. In the Trypanosomes both nuclei are equally essential and functional, 

 in somatic life as well as in sexual reproduction. 



